This relates generally to electronic devices, and more particularly, to electronic devices with displays.
Electronic devices often include displays. For example, cellular telephones and portable computers often include displays for presenting information to a user. An electronic device may have a housing such as a housing formed from plastic or metal. Components for the electronic device such as display components may be mounted in the housing.
It can be challenging to incorporate a display into the housing of an electronic device. Size and weight are often important considerations in designing electronic devices. Often when components are installed in close proximity to one another in an effort to minimize system size, components may become hot during use.
During operation of displays such as liquid crystal displays, temperature changes in liquid crystal material can lead to changes in the optical properties of the liquid crystal material. These changes can cause color casts if not corrected. For example, as a result of a decrease in the birefringence of the liquid crystal material with increasing temperature, liquid crystal displays typically become bluer as temperatures rise.
To address temperature-dependent color changes in liquid crystal displays, a temperature sensor is sometimes mounted to the back of a display. The temperature sensor may be used to estimate the temperature of the display in real time. The control circuitry for the display may then pre-distort video information loaded into the display with a color shift that compensates for the estimated temperature-induced color shift.
This type of approach may be unsatisfactory for displays that are characterized by non-uniform temperature profiles across the surface of the display. If the locations of hot system components and cooling system patterns cause temperature variations across the display, the temperature sensor on the back of the display will not be able to accurately estimate display temperature.
It would therefore be desirable to be able to provide improved temperature sensing for displays in electronic devices.